1. Fields Of The Invention
The present invention relates generally to an elapsed time hour meter which measures and indicates an amount of elapsed time, and, more particularly, to an elapsed time hour meter having a rotating counter indicator driven by an electrically powered time movement.
2. Discussion Of Background And Prior Art
a. Versatility And Reliability
Time meters that measure and indicate an amount of elapsed time are useful in many types of application. These time meters are particularly useful in keeping track of the amount of time that electrical or mechanical machinery or equipment (i.e. compressors, generators, computers, business machines, engines, etc.) have been operated, and this elapsed time information is useful to the operator in determining whether the machinery or equipment should or needs to be serviced or replaced. In order to adapt to a wide range of environments, it is important that such time meters be versatile and reliable in accurately measuring and indicating the actual amount of elapsed time. However, in order to provide such versatility and reliability, typically a large number of complex components are required to be used in the construction of the time meter. Therefore, there is a need for a time meter that has fewer and less complicated components while at the same time is still versatile and highly reliable. It is an object of the present invention to provide such a time meter.
b. Cost And Power Consumption
The use of many and complex components either drives up the cost of the time meter (i.e. more components or complex components increase the expense of the meter) or requires a higher consumption of power to operate the time meter (i.e. larger number of gears results in more friction to be overcome or more complex components require the higher power consumption). Additionally, because miniaturization also increases costs, therefore, larger sized components are often used in order to simplify the mechanisms and keep the costs of the time meter low while at the same time providing a time meter that is both accurate and reliable. However, when larger sized components are used, higher power consumption results (i.e. more torque required to move each component). Therefore, there is a need for a time meter that is not only low in cost, but also, low in power consumption. It is an object of the present invention to also fill this need.
c. Overall Size
Another factor that must be considered in designing and making a time meter is the overall size of the meter. Since the time meter may be used in an environment which has only a limited amount of physical space (i.e. a computer, miniature electronic circuit, etc.), it is desired that a small-size time meter be provided so that it can conveniently be placed and mounted in these environments. However, as stated earlier, in reducing the size of components, a manufacturer/designer must use care because miniaturization may increase the costs and/or reduce the reliability of the time meter. Therefore, there is a need for an overall small time meter that does not sacrifice low cost in achieving that dimension. It is an object of the present invention to also fill this need.
d. Prior Art
A typical prior time meter is described in U.S. Pat. No. 5,121,368 to Polydoris et al. ("'368 Patent") which discloses an engine operating time measuring apparatus. The assembly of this apparatus includes a mechanical counting apparatus driven by a quartz-crystal based clock movement mechanism. Because the time measuring apparatus incorporates the use of a clock movement, it is large in size and high in power consumption. Moreover, because this time measuring apparatus focuses on first subassembling the entire meter prior to its insertion into its housing, the apparatus requires additional components including a clock case and counter frame in order to form the subassembly. The use of these additional components further adds to the cost, complexity and large overall size of the meter.
Therefore, there is still a need for a time meter that is versatile, accurate, and reliable while at the same time generally low in cost, low in power consumption, small in size, and adapted for use in a variety of applications. The present invention overcomes these problems.